Method for treating surface of oxide glass with fluorinating agent

Abstract

To provide a novel fluorination treatment method whereby the surface of oxide glass can be treated for fluorination at low cost and with excellent adhesiveness.A method for treating the surface of oxide glass, which comprises contacting the surface of oxide glass with a gas of a fluorinating agent or a mixed gas having a fluorinating agent diluted with an inert gas, wherein the fluorinating agent is an elemental fluorine, or a fluorine compound capable of cleaving a bond between an oxygen atom and a metal atom in the framework of the oxide glass and forming a bond between a fluorine atom and the metal atom; and the concentration of hydrogen fluoride at the surface of oxide glass with which the fluorinating agent is in contact, is controlled to be at most 1 mol %.

Description

TECHNICAL FIELD[0001]The present invention relates to a method for treating the surface of oxide glass with a fluorinating agent.BACKGROUND ART[0002]There is a case where the surface of oxide glass such as soda lime glass, synthetic quartz glass, phosphate glass, borosilicate glass or alkali-free glass is desired to be treated for fluorination. For example, there is a case where the surface of such oxide glass is desired to be treated for fluorination to impart an anti-fouling property, hydrophilicity, adhesive property, moisture-proof property, anti-reflection performance, etc. to the surface of such oxide glass. In this specification, “the surface of oxide glass is treated for fluorination” means a treatment to introduce fluorine to a portion in a certain depth from the surface of oxide glass, for example, to a portion in a depth of about 2,000 nm from the surface (hereinafter, referred to as “the surface layer”).[0003]As a method for treating the surface of oxide glass for fluori...

AI Technical Summary

Benefits of technology

The present invention provides a method for fluorination treatment of oxide glass that can be carried out at low cost and with excellent adhesiveness. The method involves contacting the surface of oxide glass with a gas of a fluorinating agent or a mixed gas having a fluorinating agent diluted with an inert gas, while controlling the concentration of hydrogen fluoride at the surface of oxide glass to be at most 1 mol%. This method can be carried out in a closed container or by using a pipe line in which the gas of a fluorinating agent or the mixed gas having a fluorinating agent diluted with an inert gas continuously flows. The technical effect of this invention is that it allows for the surface of oxide glass to be treated for fluorination without deteriorating its surface properties, such as roughening and decreased light transmittance, and without excessive etching action by hydrogen fluoride.

Problems solved by technology

However, such a method utilizes a vapor deposition method, whereby there is a problem such that the adhesion of fluorine to the oxide glass is poor.

Further, the material which can be vapor-deposited is rather limited, and an expensive material is obliged to be used, whereby the production cost tends to be high.

Accordingly, the fluorine atom and the glass substrate have no chemical bond, or even if the fluorine atom and the glass substrate have a chemical bond, such a bond is only at the outermost surface of the glass substrate, whereby there is a problem such that the intended effects cannot sufficiently be obtained, or the intended effect cannot be maintained for a long period of time for such a reason that the adsorbed fluorine is likely to be easily eliminated.

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